1. Field of the Invention
The present invention relates to an information processing apparatus and method, and a computer-readable medium storing instructions for operating the information processing apparatus. Particularly, the present invention relates to a information processing apparatus and method, which can control power supplies without another controller when a plurality of power supplies are connected the information processing apparatus as input power sources of the information processing apparatus, and a computer-readable medium storing instructions for operating the information processing apparatus.
2. Description of the Related Art
In recent years, information processing apparatuses have become popular, and its importance has been increased year by year. However, there are many cases that electric power which is consumed by an information processing apparatus is directly supplied from a commercial alternating current power source, and, because of this, there are many cases that, when there occurs something wrong with the commercial alternating current power source (for example, when there occurs instantaneous lowering (instantaneous shutoff) of a voltage, sudden blackout, etc.), there occur such defects that information which is processed by an information processing apparatus at that time point is destroyed and lost, and in addition, an information processing apparatus itself (e.g., built-in hard disk etc.) is damaged.
In this connection, in order to avoid occurrence of the suchlike defects, in recent years, there are many cases that a uninterruptible power supply (UPS) is connected to an information processing apparatus (For example, see JP-A-2002-73221). This UPS, in case that a commercial alternating current power source is normal, supplies electric power from that commercial alternating current power source to an information processing apparatus, and, in case that a commercial alternating current power source is abnormal, switches its output, and can supply electric power from a built-in battery to an information processing apparatus.
By this, an information processing apparatus to which UPS was connected can use electric power which is supplied from a battery in UPS, even if there occurs something wrong with a commercial alternating current power source, and therefore, it becomes possible to continue processing as it is.
In this regard, however, a battery is a standby power supply to the bitter end, and its electric power supply capability has limitation. That is, such time that a battery is capable of outputting a voltage of a predetermined level or more (hereinafter, the suchlike time is referred to as power feedable time) has limitation. On this account, within this power feedable time, there is such a necessity that an information processing apparatus stops processing which has been carried out up to now, and carries out processing for transferring a state of itself from an operating state to such a state that it is enabled even if an input power source is cut off (hereinafter, the suchlike group of processing is referred to as shutdown processing).
Concretely speaking, for example, there are many cases that a computer etc. out of an information processing apparatus is executing application software which is operated on a predetermined OS (Operating System). In this case, the computer etc. launches its application, as the shutdown processing, and also, stores necessary data arbitrarily, and then, carries out processing for deactivating its OS.
On one hand, when discharge of a battery is carried out more than necessary, there occurs such defects that life of the battery is shortened, and it becomes unavailable for use (impossible to discharge again at a voltage with a level which satisfies a specification) even if it is charged again. On this account, there is such a necessity that, after an information processing apparatus completed the shutdown processing, as soon as possible, UPS which was connected to the information processing apparatus carries out processing for stopping discharge of a built-in battery, i.e., processing for transferring a state of the UPS from an operating state for outputting electric power to a stop state for prohibiting its output (hereinafter, the suchlike processing is referred to as UPS stop processing).
In this connection, OMRON Corporation is conducting sales of application software as shown in “Uninterruptible Power Supply Unit (UPS) Technical Manual Shutdown Software/Battery/FAQ/Successor Machine Version” written by OMRON Corporation, published by OMRON Corporation, published on Apr. 1, 2003, p.4-9 (hereinafter, the suchlike application software is referred to as shutdown software). An information processing apparatus in which this shutdown software was installed monitors a state of UPS which was connected to it, and carries out the shutdown processing, in case that there occurred something wrong with an input power source of UPS, and can have the UPS carried out the UPS stop processing.
In addition, here, in case of having focused on a predetermined apparatus, an object for supplying (inputting) electric power (regardless of whether that apparatus consumes or not) to that apparatus is referred to as an input power source. For example, as a matter stands now, UPS is focused on, and an object for supplying (inputting) electric power to that UPS is a commercial alternating current power source, and therefore, this commercial alternating current power source becomes an input power source.
As another countermeasure for an abnormality occurring at the power supply portion of an information processing apparatus, i.e., as a countermeasure that differs from the above described countermeasure, such as the connection of a UPS to an information processing apparatus, a function (hereinafter referred to as a redundant power supply function) has recently been added that provides redundancy for the power supply system of an information processing apparatus.
That is, a plurality of power units are employed for an information processing apparatus that has a redundant power supply function, and when an abnormality occurs at one of these power units, the electric power required to operate the information processing apparatus is supplied by the remaining power unit(s).
Therefore, in order to further improve the reliability of the information processing apparatus, it has been proposed that a plurality of UPSs be employed as input power sources for the information processing apparatus that has such a redundant power supply function, i.e., a plurality of UPSs are respectively connected to a plurality of power units.
However, the related-art shutdown software, as described in “Uninterruptible Electric power supply part (UPS) Technical Manual Shutdown Software/Battery/FAQ/Successor Machine Version” above, does not cope with the usage of a plurality of UPSs as input power sources for the information processing apparatus with the redundant power supply function. Therefore, when a plurality of UPSs are employed as input power sources for an information processing apparatus with the redundant power supply function, another controller, as disclosed in JP-A-2002-73221, that differs from the information processing apparatus is required to perform the shutdown processing and the UPS stop processing.